Rotary pump or motor.



T. A. KILLMAN.

ROTARY PUMP 0R MOTOR.

APPLICATION FILED ocr 13. ms

1,200,505. Patented Oct. 10,1916.

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T. A. KILLMAN.

ROTARY PUMP 0R MOTOR.

APPLICATION FILED OCT. 13. 1915.

1 ,200,505. Patented Oct. 10,1916.

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ROTARY PUMP OR MOTOR.

APPLICATION FILED OCT. 13. 1915.

1,200,505. Patented 0m. 10, 1916.

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UNITED STATES PATENT OFFICE.

THOMAS A. KILLMAN, OF NASHVILLE, TENNESSEE, ASSIGNOB T0 KILLMAN HYDRAULIC POWER TRANSMISSION COMPANY, OF TULLAHOMA, TEN- NESSEE, A. CORPORATION OF TENNESSEE.

ROTARY PUMP OR MOTOR.

Specification of Letters Patent.

Patented Oct. 10, 1916.

T 0 all whom it may concern Be it known that I, THOMAS A. KILLMAN, a citizen of the United States, residing at Nashville, in the county of Davidson and State of Tennessee, have invented certain new and useful Improvements in Rotary Pumps or Motors, of which the following is a specification.

Thls invention relates to rotary pumps or motors and has for its primary object the production of a pump or motor which will occupy little space and operate as effectively as larger motors of the construction now generally employed.

A particular object of the invention is to produce a pump or motor which will operate equally well in both directions and may be run at a high speed without perceptible vibration.

The invention is illustrated in the accompanying drawings and consists in certain novel features which will be hereinafter first fully described, and then more particularly pointed out in the claims following the description.

In the accompanying drawings: Figure 1 is a perspective view of an apparatus embodying my improvements; Fig. 2 is a section taken in a diametric lane of the same; Fig. 3 is a detail elevatlon of the piston blades; Fig. 4 is a detail section on the line 4-4 of Fig. 2; Fig. 5 is a diagram.

In carrying out my invention, I employ a substantially cylindrical casing 1 which is equipped with an end head or plate 2 having a central hub 3 projecting laterally therefrom and reinforced by rlbs 4, as will be readily understood. Any number of these cylinders of casings may be employed and in Fig. 1, I have illustrated two of such casings having a partition 5 between them and secured together by bolts 6 inserted through registering lugs 7 on the casings, the'heads and the partitions. The casing is provided with an eccentric extension 8 having a flat face 9 and through the said extenslon are formed the inlet and outlet openings or passages 1" and 11. Against the said fiat side 9, I secure the manifold 12 containmg ducts or pipes 13 through which the flu1d is admitted to and carried from the casing, as will be readily understood. It will also be understood that the device will operate as a motor or as a pump without any change in the construction, fluid being admitted under pressure to actuate the piston and thereby rotate the piston shaft when the device is operated as a motor, and power being applied to the shaft so as to rotate the piston when the device is being used as a pump and create suction through the inlet passage so as to draw fluid into the passage. By referring to Fig. 4, it will be noted that the passages 10 and 11 are not coextensive with the side wall of the casing but at the point where the said sectional figure is taken constitute each a groove in the side wall so that the base of the groove will be spaced from the edge of the pistonhlade traveling across the passage, and fluid may, consequently, flow around'the edge of the piston blade for a purpose which will presently appear. The

grooves constitute continuations of the inlet and outlet passages and are preferably arranged centrally of the side walls of the casing and define spaced guiding ribs 12 against which the ends of the piston blades bear, said guiding ribs gradually decreasing in length from their upper to their lower ends and gradually merge into the inner wall of the casing at the working space or cavity 15. It will thus be seen that the ribs form guides for the piston blades while the grooves between the ribs permit the fluid to pass around the blades so that side pressure on said blades when the latter are moving either in or out is reduced to a minimum. It will also be noted, more particularly upon reference to Fig. 2, that as the passages approach the flat side of the casing, they become in form and efl'ectpi es or inclosed openings extending substantiaIly tangential to the casing so that the fluid will be prevented from encircling the piston but will be directed to and from the same in the desired manner.

The piston 13 is circular and is secured rigidly to the shaft 14 in any desired manner, the said shaft being rotatably mounted in the hubs or projections 3 of the cylinder heads. The said hub is disposed eccentrically to the casing and, consequently, the piston is mounted eccentrically within the easing so that the piston and the casing are close together between the passages 10 and 11, and, at a point diametrically opposite the, space between said passages, the iston and easing are separated so as to a 0rd a working space or cavity 15 substantially of a crescent form. The piston is constructed with radial notches or grooves 16 disposed one diametrically opposite and in alinement with another and with one pair of the notches or grooves at right angles to another pair of notches or grooves. Within these radial notches or grooves, I slidably mount the blades 17 having grooved outer edges in which are fitted packing strips 18 of any suitable material and which will preferably rest against springs seated between the packing and the body of the blades so as to hold the blades positively and evenly against the wall of the casing. Diametrical passages are formed in the pistons and in these passages are slidably mounted plungers or connecting rods 19 which have their opposite ends bearing against the inner edges or ends of opposite blades. It will thus be readily understood that, as the piston rotates, the blades riding upon the inner wall of the casing will be caused to successively project beyond the periphery of the piston and then be withdrawn into the piston, the connecting rod or plunger causing the receding blade to positively project the blade alined therewith.

The inner wall of the casing is not a true circle, as will be very readily understood upon reference to Fig. 5, in which figure the circle 20 represents the outline of the piston described about the center 21. The dotted circle 22 is a true circle described about a center eccentric to the center 21 and it will be noted that this true circle touches the line 23 at the top and the bottom of the fi ure and defines what would be the outline o the inner wall of the casing if said wall were formed upon a true circle but eccentric to the piston. The line 23 represents the outline of the inner wall of the casing, as I construct the same, and it will be noted that between the points 24 and 25 and between the points 26 and 27 this outline is an arc of a circle having the point 21 as its center, while between the points 24 and 26 and between the points 25 and 27 the wall of the casing follows an irregular curve, producing a cam surface against which the piston blades ride to be projected or withdrawn. By referring to Fig. 2, it will be understood that the inner openings or ends of the passages 10 and 11 extend between the points 24 and 26 and the points 25 and 27 respectively, and follow the outline of said irregular curves. The straight lines 28 in Fig. 5 indicate the positions of the pistons at successive stages of the operation, and it is obvious that these lines are all the same length.

In operation, as the piston revolves, the blades will be carried over the face of the casing between the points 24 and 25, across the space between the points 24 and 26, over the face of the casing between the points 26 and 27 and across the space between the points 25 and 27. Between the points 24 and 25 and the points 26 and 27 the blades will form sealed joints with the casing as the packing will bear against the entire longitudinal extent of the wall of the casing and, consequently, these spaces will be working spaces, and are arcs of true concentric circles so that, when the blades are moving over said arcs, they do not move in nor out and, therefore, create no friction upon their side edges. As a blade moves across the passage 10, for instance, it will be projected from the piston, but as the passage permits the fluid to flow around the edge of the piston blade, the blade is not at this time working and will not become a working blade until it has reached the extreme end of the passage and forms a sealed joint with the walls of the casing. It will thus be seen that, when the blade is moving in or out, it is not a working blade, so that there is no loss of power, due to the friction created by the blades moving inwardly or outwardly while they are at work. It will also be noted, upon reference to Fig. 5, and by comparison of the circle 22 with the line 23, that, while the blades move in and out relative to the'piston, the outer ends of the blades do not deviate a great deal from a true circle, so that the machine can run at a high speed without vibration.

It is obvious that the device may be operated either as a pump or as a motor and that as many casings may be provided as may be desired for the particular work to be performed, a piston being mounted within each casing and a shaft common to all the pistons being extended through all the casings and journaled in the heads upon the end casings.

Having thus described the invention, what is claimed as new is:

1. A device of the class described including a casing having inlet and outlet ports arranged on the same side thereof, the inner wall of the casing being formed upon arcs of concentric circles at diametrically opposite portions and having irregular cam surfaces connecting said portions, there being grooves formed in the cam surfaces and communicating with the ports, said grooves defining spaced guiding ribs having their inner opposing faces parallel-and gradually merged into the inner wall of the casing, a piston rotatably mounted within the casing eccentrically thereto and disposed concentrically with said arcuate portions, and blades slidably mounted in the piston and adapted to bear against the edges of said guiding ribs.

2. A device of the class described comprising a casing having inlet and outlet ports arrangedon the same side thereof, said casing having diametrical portions of its inner wall formed upon concentric circles of different radu and having cam portions connecting said concentric portions, there being grooves formed in the cam portions and communicating with the ports, said grooves defining spaced guiding ribs having their inner opposing faces parallel and gradually decreasing in depth from the ports to the lower portion of the casing and having their lower ends gradually merged into the inner wall of the casing, a rotary piston mounted within the casing concentric with the concentric portions of said casing and close to one of said portions, and blades'carried by said piston and adapted to ride upon the inner wall of the casing and upon the edges of said guiding ribs.

3. A device of the class described including a casing having an extension provided with a flat face formed with inlet and outlet ports, said casing having diametrical portions of its in er wall formed upon concentric circles 0 different radii and having cam portions connecting said concentric portions, there being grooves formed centrally in the cam portions and passing through the extension of the casing and communicating with the ports, said grooves defining spaced guiding ribs having their inner opposing faces parallel and gradually decreasing in depth from the ports to the lower portion of the casing and having their lower ends gradually merged into the inner wall of the casing, a manifold fitting the flat face of the extension and provided with inlet and'outlet pipes communicating with the ports, a cylindrical piston mounted eccentrically within the casing, and blades carried by the piston and adapted to ride upon the inner wall of the casing and upon the edges of the I guiding ribs.

In testimony whereof, I affix my signa ture.

THOMAS A. KILLMAN. FL. 5.] 

